Pneumatic motor



Jam l5 1924.

- A. GOTTSCHALK PNEUMATIC MOTOR Filed Aug. 6, 1918 CCC C fizz e72 tar W (BF-wk WW Jhmy Fatented Jan. 15, 3224..

ALBERT GOTISCH, OF NEW YGRIK, N. Y., ASSIGNOR TO NAI'IGNAL PMiliiIC GOMPANY, OF NEW YORK, TN. I, A CORPORATION OF T VIRGINIA.

?NEUMATIC MOTOR.

Application filed August 6, 1918. Serial No. 248,352.

To all whom it may concem:

Be it known that I, ALBERT GorrsoHAnK, a citizen of the United States, residi g at New York, county and State of New ork,

have made a certain new and useful Invention in Pneumatic Motors, of which the following is a specification.

This invention relates to pneumatic motors, and particularly to motors of this type utilized principally for the operation ofi doors on cars, street cars, or the like.

The object of the invention is to provide a pneumatic motor which is simple in construction, eflicient in operation, and economical of manufacture, and which requires little or no care or attention in upkeep.

A further object of the invention is to provide a motor ofthe character described utilizing the control'f tjhereof for securing proper cushioning of the motor at the limit of its working strokes.

Further ob ects of the invention will appear more fully hereinafter.

The invention consists substantially in the construction, combination, location, relative arrangement of parts, all as will. be more "fully hereinafter set forth, as shown by the accompanying drawing, and finally pointed out in the appended claims.

Referring to the drawing Fig. 1 is a view in section of a motor embodying my inventionshowin diagrammatical y the piping layout use in connection therewith.

Fig. 2 is an enlarged sectional view of one head used with the motor of my invention.

The same part is designated by the same reference character wherever it occurs throughout the several views;

1 designates generally a pneumatic motor of the usual construction, compnsmg cylinders 2 and 3, within which operate pistons 4 and 5,the cylinder and piston 2 and 4 respectively being of difierent size than the cylinder and piston 3 and 5, thus const1tuting a 'diiierential type of motor. The respective pistons are connected bymeans of the piston rod 6 provided with the teeth 7 which mesh with and engage the segment gear 8 which is mounted on a shaft 9 and to which is secured the arm 10 for actuation of the door or the part to be moved. This is the usual construction of differential piston type of pneumatic motors. Fluid pressure is admitted through the ipe line 20 and through the line 21 to tiie casing 1 and through head 22 to a small port in front of the piston'5. It will beseen therefore that pimon 5 is at all times in communication with the source of fluid pressure. A joint line 23 communicates at all times with line 24, which communicates with the head 25 of the larger cylinder through a plug 26 to the chamber 27, which is controlled by a valve 28, the sides of which valve are grooved as indicated at 29 to, in the posit10n shown, established communication between the chamber 27 and a passage 30.

The passage 30 communicates through a small port 60 with the end of the cylinder 2, and through passage 31 and port 32 with the opposite end of the cylinder 2, port 32 being controlled in any suitable manner, for example, by means of a ball and check as indicated at 33. The continuation of the line 23 is controlled by a valve 40,which valve may be controlled in any suitable manner, for instance, manually, by means of the handle 41, so that when the valve is in one position communication is established between the line 23 and the line 42, and when the handle is turned in the other direction, for

example, as shown, the line 42 is opened to exhaust through port 43 in the valve case 44. The line 42 leads to the casting 1 and through passage 45 to one end of the chamber 46 behind a piston 47 located within said chamber. The piston 47 is provided with plungers 48 adapted to bear against one end of the valve 28 to move the same in the chamber 27, it being understood that when the valve 28 is in the position as shown in Fig. 2 communication between the passage 30 and line 24 is established,"and communication between the passage 3Q and the exhaust port 50 located in the head 25 communicating with the atmosphere is shut 0E. Likewise when the valve 28 is inits opposed position communication between thelline' 24 and the passage 30 is shut ed and communication between passage 30 and the exhaust'port 50 is established. With the parts as shown and the valve 40 in the position indicated, it will be seen that any pressure that might be located behind the," piston 47 isteahausted through passage 45,1ine 42, through the valve 40,exhaust port 43 of the valve casing 44,

and fluid pressure passing from supply line 20, line 21, is constantly behind the piston 5,

and at the same time through line 23 and 24, chamber 27, groove 29 of the. valve 28, passage 30, port 60. Pressure is likewise admitted behind piston 4, and the piston 4 being of larger diameter than piston 5, the pressure on the ends thereof is unequal and consequently the parts assume the position shown, that is, .for example, with the door closed. The minute, however, the valve 40 is shifted to establish communication between the lines 23 and 42 the following operation takes place-fluid pressure passes from the line 23 through valve 40, line 42, passage45, behind the piston 47 causing the same to move upwardly in its chamber 46 and the plungers 48 thereof closing the passage leading from line 24 to chamber 27 and establishing communication between passage 30 and exhaust'port 50 of the head 25. There will be instantly a comparatively large exhaust through port 32 raising the check valve 33 and therefrom through passages 31 and 30 to exhaust 50 allowing the pressure behind the piston5 to cause the piston to move to the left in their cylinders. As soon, however, as the piston 4 passes by the port 32 the only egress for the pressure contained in the cylinder 2 is through restricted port 60 of passage 80 and thus the closing movement of the motor will be effectively cushioned and will prevent the slam-.

ming of the door, etc. So long as the valve 40 remains in the position indicated the motor will be maintained in its position thus secured. As soon, however, as the valve 40 is shifted to again establish communication between lines 23 and 42 fluid pressure will again be admitted behind the piston 4, and as the diameter thereof is larger than the diameter of the piston 5 the motor will be moved in the opposite direction, the cushioning effect of this structure of the motor being secured by the face of the piston 5 being constantly exposed to the fluid pressure through the line 21 as hereinbefore described. It will be seen that I have thus secured a very simple pneumatic motor and control thereof requiring but few parts and meeting the requirements of efi'ectivel cushioning at the limits of its strokes. it may be advisable and necessary to secure a reversal of the motor under certain circumstances, for example, when utilized in connection with door operation if an obstruction is met in the closing of the door. Consequently I have shown the under sur face of the piston 47 in the motor head 25 as being in connection through the line with a suitable source of pressure (not shown), which may be controlled in any desired or well known manner for efi'ecting a reversal of the motor either during its operation or efiecting an actuation of the m0- 'oylin ers, a cylinder head tor if the same is at rest when fluid pressure is supplied through the line 70 independentl of the manually controlled valve 40.

any changes and modifications will readily occur to those skilled in the art without departing from the spirit and scope of my invention as defined in the claims, therefore what I claim as new and useful, and of my own invention, and desire to secure by Letters Patent, is, i

l. A pneumatic motor ential cylinders, a piston for each of said cylinders, a piston rod connecting said pistons, means for normally maintaining a supply of fluid pressure to both of said cylinders, a valve for controlling the supply comprising difl'erof fluid pressure to, and the exhaust of the same from the cylinder of larger diameter for initiating the operation of said motor, and fluid pressure actuated means for shifting said valve.

2. A pneumatic motor entialcylinders, a piston for each of said cylinders, a piston rod connecting said pistons, means for normally maintalning a supply of fluid pressure to both of said cylinders, a valve for controlling the su ply of fluid pressure to, and the exhaust 0t the same from the cylinder of larger diameter for initiating the operation of said motor,

comprising differand manually controlled fluid pressure actuated means for shifting said valve.

3. A pneumatic motor comprising-difler ential cylinders, a piston for each of said cylinders, a piston rod connecting said pistons, means for normally maintaining 9. Suppl of fluid pressure toboth of said for the cylinder of larger diameter and provided with passages communicating with the exhaust and through a restricted port with the cylinder, a valve located in said head for controlling said passa es to shut off the pressure supply to the cy inder and simultaneously open said cylinder to exhaust, and a free exhaust passage communicating with said passages and with said cylinder at a point intermediate its ends.

4. A pneumatic motor comprising differential cylinders, cylinders, a piston rod connecting said pistons, means for normally maintaining a supply of fluid pressure to both of said cylinders, a cylinder head for the cylinder of larger diameter and provided with passages communicating with the exhaust and through a restricted port with the cylinder, a valve located in said head for controlling said passages to shut of the pressure supply to the cy inder and simultaneously open said cylinder to exhaust, and a free exhaust passage communicating with said passages and with said cylinder at a point intermediate its ends, and means for controlling said valve.

a piston for each of said 5. A pneumatic motor comprising difier ential cylinders, a piston for each of said cylinders, a piston rod connecting said pistons, means for normally'maintaining a supply of fluid pressure to both of saidcylinders, a cylinder head for the cylinder of larger diameter, and provided with passages communicating with the exhaust and through a restricted port, with the cylinder, a valve located in said head for controlling said passages to shut ofi' the pressure supply to the cylinder and simultaneously open said cylinder to exhaust, and a free exhaust passage communicating with said passages and with said cylinder at a point intermediate its ends, and fluid pressure actuated means for controlling said 'valve.

6. A pneumatic motor comprising difi'erential cylinders, a piston for each of said.

cylinders, a piston rod connecting said pistons, means for normally maintaining a supply of fluid pressure to both of said cylinders, a cylinder head forthe cylinder of larger diameter and provided with passages communicating with the exhaust and through a restricted port with the cylinder, a valve located in said head for controlling said passages to shutofi the pressure supply to the cylinder and simultaneously open said cylinder to exhaust, and a free exhaust passage communicating with said passages and with said cylinder at a point intermediate its ends,: and manually controlled fluid pressure actuated means for controlling said valve.

7. A pneumatic motor comprising difierential cylinders, a piston ,for each of said cylinders, a piston 1 rod connecting said pistons, means for normally maintaining a supply of fluid pressure to both of said cylinders, a cylinder head for the cylinder of larger diameter and provided with passages communicating with the exhaust ,and through a restricted port with the cylinder, a valve located in said head for controlling said passages to shut off the pressure supply to the cylinder and simultaneously open said cylinder to exhaust, and a free exhaust passage communicating with said passages and with said cylinder at a point intermediate its ends, and a check valve for said auxiliary passage.

In testimony whereof I have hereunto set my hand on this 23rd day of July A. D.,

19 18. i s i ALBERT GOTTSCHALK. 

